New estimates from the World Health Organization suggest 7 million premature deaths a year are because of air pollution.
That’s one in eight of total global deaths, more than double previous estimates, according to the UN’s public health arm.
It claims air pollution is now the world’s largest single environmental health risk and that reducing air pollution could save millions of lives.
Researchers say they now have a better idea of how people are exposed to air pollution outdoors, using satellite images and models on how pollution drifts in the air.
They applied this to the latest WHO mortality data from 2012 to get the new estimates.
It is accepted that inhaling smoke from burning wood or coal on cooking stoves has a health impact but the new research reveals a stronger link between both indoor and outdoor air pollution to cardiovascular diseases.
Dr Maria Neira, Director of WHO’s Department for Public Health, Environmental and Social Determinants of Health said: “The risks from air pollution are now far greater than previously thought or understood, particularly for heart disease and strokes.”
The worst faring region appear to be low and middle income countries in South East Asia and Western Pacific, with 3.3 million deaths linked to indoor air pollution and 2.6 million deaths related to outdoor air pollution.
Women and children are especially vulnerable, according to Dr Flavia Bustreo, the WHO’s Assistant Director-General for Family, Women and Children’s Health.
She said: “Poor women and children pay a heavy price from indoor air pollution since they spend more time at home breathing in smoke and soot from leaky coal and wood cook stoves.”
Dr Bustreo added that cleaning up the air we breathe would prevent “non-communicable diseases” as well as slash disease risks among women, children and the elderly.